Does anyone know what selecting "factory" does in fastboot?

[AC Question]

Motorola Droid Ultra Android version 4.4.4. After entering the fastboot menu (vol down and power key) there are options for "normal power up", "recovery", "factory", "barcodes", and "BP Tools". Can anyone explain what selecting factory or barcodes or BP tools does? Specifically i want to know about factory. I am looking for a way to reset my phone to the way it was when i bought it INCLUDING resetting to the original version of android it came with.

 

[cpaight]

A factory reset will completely wipe your device of all apps, pics, contacts, settings, etc....but it won't revert back to a previous version of Android if you've already installed a newer one.